DE1210765B - Use of a paste to produce a porous membrane for gas separation carried by a metal mesh - Google Patents

Use of a paste to produce a porous membrane for gas separation carried by a metal mesh

Info

Publication number
DE1210765B
DE1210765B DEC17664A DEC0017664A DE1210765B DE 1210765 B DE1210765 B DE 1210765B DE C17664 A DEC17664 A DE C17664A DE C0017664 A DEC0017664 A DE C0017664A DE 1210765 B DE1210765 B DE 1210765B
Authority
DE
Germany
Prior art keywords
paste
alcohol
metal mesh
gas separation
porous membrane
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
DEC17664A
Other languages
German (de)
Inventor
Jean Parisot
Gilberte Moutaud Geb Renault
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Commissariat a lEnergie Atomique et aux Energies Alternatives CEA
Original Assignee
Commissariat a lEnergie Atomique CEA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from FR749440A external-priority patent/FR72740E/en
Application filed by Commissariat a lEnergie Atomique CEA filed Critical Commissariat a lEnergie Atomique CEA
Publication of DE1210765B publication Critical patent/DE1210765B/en
Pending legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08JWORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/28Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof by elimination of a liquid phase from a macromolecular composition or article, e.g. drying of coagulum
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D39/00Filtering material for liquid or gaseous fluids
    • B01D39/10Filter screens essentially made of metal
    • B01D39/12Filter screens essentially made of metal of wire gauze; of knitted wire; of expanded metal
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D53/00Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/22Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by diffusion
    • B01D53/228Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by diffusion characterised by specific membranes
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D71/00Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
    • B01D71/06Organic material
    • B01D71/30Polyalkenyl halides
    • B01D71/32Polyalkenyl halides containing fluorine atoms
    • B01D71/36Polytetrafluoroethene
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/06Fibrous reinforcements only
    • B29C70/10Fibrous reinforcements only characterised by the structure of fibrous reinforcements, e.g. hollow fibres
    • B29C70/16Fibrous reinforcements only characterised by the structure of fibrous reinforcements, e.g. hollow fibres using fibres of substantial or continuous length
    • B29C70/20Fibrous reinforcements only characterised by the structure of fibrous reinforcements, e.g. hollow fibres using fibres of substantial or continuous length oriented in a single direction, e.g. roofing or other parallel fibres
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08KUse of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K5/00Use of organic ingredients
    • C08K5/04Oxygen-containing compounds
    • C08K5/05Alcohols; Metal alcoholates
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00Stock material or miscellaneous articles
    • Y10T428/31504Composite [nonstructural laminate]
    • Y10T428/31511Of epoxy ether
    • Y10T428/31529Next to metal
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00Stock material or miscellaneous articles
    • Y10T428/31504Composite [nonstructural laminate]
    • Y10T428/31678Of metal
    • Y10T428/31692Next to addition polymer from unsaturated monomers
    • Y10T428/31696Including polyene monomers [e.g., butadiene, etc.]
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T442/00Fabric [woven, knitted, or nonwoven textile or cloth, etc.]
    • Y10T442/20Coated or impregnated woven, knit, or nonwoven fabric which is not [a] associated with another preformed layer or fiber layer or, [b] with respect to woven and knit, characterized, respectively, by a particular or differential weave or knit, wherein the coating or impregnation is neither a foamed material nor a free metal or alloy layer
    • Y10T442/2926Coated or impregnated inorganic fiber fabric

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Medicinal Chemistry (AREA)
  • Textile Engineering (AREA)
  • Organic Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Health & Medical Sciences (AREA)
  • Composite Materials (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)
  • Treatments For Attaching Organic Compounds To Fibrous Goods (AREA)
  • Laminated Bodies (AREA)

Description

BUNDESREPUBLIK DEUTSCHLANDFEDERAL REPUBLIC OF GERMANY

DEUTSCHESGERMAN

PATENTAMTPATENT OFFICE

AUSLEGESCHRIFTEDITORIAL

Int. Cl.:Int. Cl .:

Nummer:
Aktenzeichen:
Anmeldetag:
Auslegetag:
Number:
File number:
Registration date:
Display day:

D06nD06n

Deutsche Kl.: 81-4German class: 81-4

1210765
C17664IVC/81
13. Oktober 1958
17. Februar 1966
1210765
C17664IVC / 81
October 13, 1958
17th February 1966

Gegenstand des Patents 1149 689 ist ein Verfahren zur Herstellung einer von einem Metallgewebe getragenen porösen Membran zur Gastrennung, insbesondere Isotopentrennung. Dabei wird das Metallgewebe mit einer Paste bestrichen, die man durch Koagulieren einer Emulsion von Polytetrafiuoräthylen oder Polytrifluorchloräthylen mittels eines Koagulationsmittels herstellt. Durch einen Walzvorgang wird die Paste derart mit dem Gewebe verfestigt, daß sie das Gewebe gleichförmig umhüllt und die Maschen ausfüllt; das Koagulationsmittel wird darauf aus dem so bestrichenen Gewebe durch eine Behandlung bei einer Temperatur entfernt, die 300° C nicht wesentlich übersteigt.The subject of patent 1149 689 is a method for producing one of a metal mesh supported porous membrane for gas separation, in particular isotope separation. This is where the metal mesh coated with a paste obtained by coagulating an emulsion of polytetrafluoroethylene or polytrifluorochloroethylene by means of a coagulant. By a rolling process the paste is solidified with the tissue in such a way that it envelops the tissue uniformly and the Fills meshes; the coagulant is then removed from the thus coated tissue by a treatment removed at a temperature not significantly exceeding 300 ° C.

Die vorliegende Erfindung betrifft eine für die Zwecke des Hauptpatents geeignete Paste.The present invention relates to a paste suitable for the purposes of the main patent.

Gemäß der Erfindung wird zum Bestreichen des Metallgewebes der Membran eine Paste verwendet, die aus einem Gemisch von Polytetrafmoräthylenpulver und Alkohol besteht, wobei der Gewichtsanteil des Alkohols 40% beträgt. Die Wirkung des Alkohols bei der Herstellung der Paste ist die eines organischen Netzmittels; es hat die rein physikalische Aufgabe, das Polytetrafluoräthylenpulver in eine Paste umzuwandeln, die leicht auf das Grundgewebe aufgebracht werden kann, worauf es nach Fixierung der Paste aus dem Gewebe wieder ausgeschieden wird.According to the invention, a paste is used to coat the metal fabric of the membrane, which consists of a mixture of polytetrafluoroethylene powder and alcohol, the proportion by weight of alcohol being 40%. The effect of the The alcohol used in the preparation of the paste is that of an organic wetting agent; it has the purely physical Task to convert the polytetrafluoroethylene powder into a paste that is easily applied to the base fabric can be applied, whereupon it is excreted from the tissue after fixation of the paste will.

Gemische von Polytetrafluoräthylen mit Alkohol in verschiedenen Mengenverhältnissen sind an sich bekannt; es war aber nicht vorauszusehen, daß derartige Gemische sich besonders zur Herstellung einer Paste eignen, wie sie bei der Membranherstelllung gemäß dem Hauptpatent benötigt wird.Mixtures of polytetrafluoroethylene with alcohol in various proportions are per se known; but it was not foreseeable that such mixtures would be particularly suitable for the production of a Paste suitable, as it is required in the membrane production according to the main patent.

Als geeignete Alkohole kommen in Frage: Äthylalkohol, Methylalkohol, Isopropylalkohol, Butylalkohol, Isobutylalkohol, Isoamylalkohol, Cyclohexanol. Suitable alcohols are: ethyl alcohol, methyl alcohol, isopropyl alcohol, butyl alcohol, Isobutyl alcohol, isoamyl alcohol, cyclohexanol.

Die Anteile ^es Gemisches müssen so gewählt sein, daß sich die Paste leicht auftragen läßt, d. h., sie muß gut formbar und homogen sein, ohne zu flüssig zu werden oder zu fließen.The proportions of the mixture must be chosen in this way be that the paste is easy to apply, d. that is, it must be easily malleable and homogeneous without to become fluid or to flow.

Nachstehend ist ein Ausführungsbeispiel für die Anwendung der Paste gemäß der Erfindung beschrieben: das Polytetrafluoräthylenpulver, das von einer Polytetrafluoräthylenemulsion stammt, wird im überschüssigen Alkohol kräftig geknetet (z. B. 100 g Pulver für 300 cm3 Alkohol). Nach vollkommener Homogenisierung der Paste wird diese so ausgeschleudert, daß nur ungefähr 40 Gewichtsprozent Alkohol übrigbleiben.An exemplary embodiment for the use of the paste according to the invention is described below: the polytetrafluoroethylene powder, which comes from a polytetrafluoroethylene emulsion, is kneaded vigorously in the excess alcohol (e.g. 100 g of powder for 300 cm 3 of alcohol). After the paste has been completely homogenized, it is centrifuged in such a way that only about 40 percent by weight of alcohol remains.

Die so ausgeschleuderte Paste wird auf das Metall-The paste that is thrown out in this way is

Verwendung einer Paste zum Herstellen einer von einem Metallgewebe getragenen porösen
Membran zur Gastrennung
Use of a paste to produce a porous one supported by a metal mesh
Membrane for gas separation

Zusatz zum Patent: 1149 689Addendum to the patent: 1149 689

Anmelder:Applicant:

Commissariat ä l'Energie Atomique, ParisCommissariat a l'Energie Atomique, Paris

Vertreter:Representative:

Dr. phil. W. P. Radt, Patentanwalt,Dr. phil. W. P. Radt, patent attorney,

Bochum, Heinrich-König-Str. 12Bochum, Heinrich-König-Str. 12th

Als Erfinder benannt:Named as inventor:

Gilberte Moutaud, geb. Renault,Gilberte Moutaud, née Renault,

Neuilly-sur-Seine, Seine;Neuilly-sur-Seine, Seine;

Jean Parisot, Argenteuil, Seine-et-OiseJean Parisot, Argenteuil, Seine-et-Oise

(Frankreich)(France)

Beanspruchte Priorität:
Frankreich vom 15. Oktober 1957
Claimed priority:
France October 15, 1957

gewebe aufgebracht und hierauf entsprechend dem in dem Hauptpatent beschriebenen Verfahren gewalzt und behandelt.tissue applied and then rolled in accordance with the method described in the main patent and treated.

Vor dem Aufbringen und zur Erzielung einer besseren Tränkung der Paste durch den Alkohol kann die Paste einer Alterung unterworfen werden, indem sie in ein kochendes Alkoholbad eingetaucht wird, worauf ein neues Ausschleudern bis zum Erhalt der obigen Anteilmengen erfolgt.Before application and to achieve better impregnation of the paste with the alcohol the paste can be aged by immersing it in a boiling alcohol bath is, whereupon a new spinning takes place until the above proportions are obtained.

Vor der Aufbringung können noch die Spuren der ursprünglich in dem Polytetrafluoräthylenpulver enthaltenen organischen Verunreinigungen ausgeschieden werden. So können z. B. die noch vorhandenen Netzmittelspuren durch Ausziehen im Soxhlet-Apparat oder besser mit einem Ausziehgerät entfernt werden, in welchem die Paste beständig in einem lauwarmen Alkoholbad umgerührt wird.Before the application, the traces of the originally in the polytetrafluoroethylene powder contained organic impurities are excreted. So z. B. the remaining ones Traces of wetting agent removed by pulling out in the Soxhlet apparatus or, better still, with an extractor in which the paste is constantly stirred in a lukewarm alcohol bath.

Die nachstehende Tabelle zeigt beispielsweise die Kenngrößen von fünf Proben von erfindungsgemäß hergestellten Membranen:The table below shows, for example, the characteristics of five samples according to the invention produced membranes:

Dicke· in Hundertstelmillimeter;
Porenhalbmesser in Hundertstelmikron;
Thickness · in hundredths of a millimeter;
Pore radius in hundredths of a micron;

609 508/217609 508/217

Durchlässigkeit in Grammolekül Luft, welche je Quadratzentimeter der Membran je Minute für einen Druckunterschied beiderseits der Membran von 1 cm Hg gehen.Permeability in gram molecule of air, which per square centimeter of the membrane per minute go for a pressure difference on both sides of the membrane of 1 cm Hg.

Probesample Dickethickness Poren-
• halbmesser
Pore
• half-knife
DurchlässigkeitPermeability
1
2
3
4
5
1
2
3
4th
5
40 + 5
41 + 4
40 + 2
40 + 3
39 + 2
40 + 5
41 + 4
40 + 2
40 + 3
39 + 2
1
1
1
1
2
1
1
1
1
2
58-10-7
78 · 10-7
78 · ΙΟ"7
110·ΙΟ"7
112-10-7
58-10-7
78 · 10-7
78 · ΙΟ " 7
110 · ΙΟ " 7
112-10-7

Claims (1)

4 '
Patentanspruch:
4 '
Claim:
Verwendung einer Paste, die aus einem Gemisch von Pplytetrafluoräthylenpulver und Alkohol besteht, wobei der Gewichtsanteil des Al-Use of a paste made from a mixture of polytetrafluoroethylene powder and alcohol consists, where the weight fraction of the Al- " kohols 40% beträgt, zum Herstellen einer von ,einem Metallgewebe getragenen porösen Membran zur Gastrennung, insbesondere Isotopen-"alcohol is 40% for the production of a porous membrane supported by a metal mesh for gas separation, especially isotope " trennung, nach Patent 1149 689."separation, according to patent 1149 689. In Betracht gezogene Druckschriften:
USA.-Patentschrift Nr. 2440190;
französische Patentschrift Nr. 928 293;
britische Patentschriften Nr. 589 714, 638 328.
Considered publications:
U.S. Patent No. 2440190;
French Patent No. 928 293;
British Patent Nos. 589 714, 638 328.
609 508/217 2.66 © Bundesdruckerei Berlin609 508/217 2.66 © Bundesdruckerei Berlin
DEC17664A 1956-05-22 1958-10-13 Use of a paste to produce a porous membrane for gas separation carried by a metal mesh Pending DE1210765B (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR714914 1956-05-22
FR749440A FR72740E (en) 1956-05-22 1957-10-15 Porous membranes and method of manufacturing these membranes

Publications (1)

Publication Number Publication Date
DE1210765B true DE1210765B (en) 1966-02-17

Family

ID=37663303

Family Applications (1)

Application Number Title Priority Date Filing Date
DEC17664A Pending DE1210765B (en) 1956-05-22 1958-10-13 Use of a paste to produce a porous membrane for gas separation carried by a metal mesh

Country Status (7)

Country Link
US (1) US3102826A (en)
BE (1) BE571757A (en)
DE (1) DE1210765B (en)
DK (1) DK102792C (en)
GB (1) GB863744A (en)
LU (1) LU36469A1 (en)
NL (1) NL122519C (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2208632C3 (en) * 1972-02-24 1981-07-30 Battelle-Institut E.V., 6000 Frankfurt Process for the production of carbon-containing gas electrodes with a hydrophobic backing layer
US3920793A (en) * 1973-04-02 1975-11-18 Du Pont Corrosion-resistant perfluorocarbon polymer coated metal substrate and process for preparing the same

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB589714A (en) * 1944-03-29 1947-06-27 Ici Ltd Fabrication of articles consisting essentially of a polymer of tetrafluoroethylene
FR928293A (en) * 1944-03-01 1947-11-24 Du Pont Manufacturing process of polytetrafluoroethylene sheets and other articles and resulting products
GB638328A (en) * 1946-12-07 1950-06-07 Du Pont Moulding powders comprising fluorine-containing polymers

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2813041A (en) * 1953-09-09 1957-11-12 Glacier Co Ltd Method of impregnating porous metal strip with polytetrafluoroethylene
US2710266A (en) * 1953-12-21 1955-06-07 Du Pont Polytetrafluoroethylene coating compositions, method of application to substrates, coated substrates, and films
US2866721A (en) * 1955-03-15 1958-12-30 Minnesota Mining & Mfg Dispersion of fluorochlorocarbon polymers in a solution of a copolymer of trifluorochloroethylene with a halogenated olefin and method of coating surface therewith

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR928293A (en) * 1944-03-01 1947-11-24 Du Pont Manufacturing process of polytetrafluoroethylene sheets and other articles and resulting products
US2440190A (en) * 1944-03-01 1948-04-20 Du Pont Preparation of nonporous polytetrafluoroethylene articles
GB589714A (en) * 1944-03-29 1947-06-27 Ici Ltd Fabrication of articles consisting essentially of a polymer of tetrafluoroethylene
GB638328A (en) * 1946-12-07 1950-06-07 Du Pont Moulding powders comprising fluorine-containing polymers

Also Published As

Publication number Publication date
DK102792C (en) 1965-10-11
US3102826A (en) 1963-09-03
LU36469A1 (en)
NL122519C (en) 1900-01-01
BE571757A (en) 1900-01-01
GB863744A (en) 1961-03-29

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